GSoC 2018: SymPy - Week 12

The final week of Coding Period has completed.

This week, the work was mainly concerned with the documentation and refinements in the discrete module.
I started by opening PR #14994 to update Sphinx docs for SymPy.
Kalevi and Aaron were kind enough to review the PR and help refine it for the final merge. The documentation for discrete module is now part of the SymPy docs and can be referred here.

Late this week, I opened PR #15025 for improvements in the discrete module.
Colin helped fix accidental floats in unit tests (which should have been Rationals). After the review, the PR was merged successfully.

Future work would include - addition of a user-facing public method for linrec and making methods fft and convolution_fft efficient for both symbolic and numeric variants, as some discussion and benchmarking has been done for it and there is some work done by Colin for ComplexFloat class in PR #12192 which would be helpful for the same.

Looking forward to the concluding phase, where I will be wrapping up GSoC and preparing the report for the final evaluation.